


Never Count the Cost

by LadyHallen



Category: Harry Potter - J. K. Rowling, Katekyou Hitman Reborn!
Genre: Alternate Universe - Canon Divergence, Angst or is it?, Crossover, Demon Reborn, Demon Summoning, F/M, Female Harry Potter, Genderbend
Language: English
Status: Completed
Published: 2020-11-13
Updated: 2020-11-13
Packaged: 2021-03-10 05:55:16
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,002
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27539479
Author URL: https://archiveofourown.org/users/LadyHallen/pseuds/LadyHallen
Summary: “Harry,” she began slowly. “I don’t know how to tell you this, but I think a chaos demon just propositioned you.”
Relationships: Harry Potter/Reborn (Katekyou Hitman Reborn!), Hermione Granger & Harry Potter & Ron Weasley
Comments: 57
Kudos: 962





	Never Count the Cost

**Author's Note:**

> I had a dream about demon Reborn and wrote it because I wanted to know how it would end too.

It was hopeless.

The Death Eaters numbers weren’t going down. And maybe they were, but not visibly, not enough. Kill one Death Eater, and five more would take their place.

Hermione had given people new, more destructive spells and Ron’s strategies were getting more and more geared towards mass destruction. But it wasn’t good enough.

It shot down morale and everyone was getting desperate.

 _Harry_ was getting desperate.

She’d asked Kreacher, which was the start of a series of bad decisions.

Kreacher knew the Black Library better than anyone, and gave Harry a book bound in questionable leather.

Harry took one look at the book, and felt her skin crawl. She decided not to ask the house-elf questions.

“Thank you, Kreacher,” she said.

She read the book when it was supposed to be her turn to be sleeping, and lost her appetite at the horrifying and terrible rituals that the book had. She was pale and unhappy reading the rituals.

Still she found one. One ritual among hundreds that suited her purpose. A ritual to **_“Summone a Moste Powerful and Chaotic Monstere.”_**

Harry read it dozens of times, memorized the words and knew the sacrifice.

Desperation and bad decisions led her to the forest with a stone floor. She had left a note with Dean, hopefully, it would stall her friends.

Her hands remained determinedly steady even as she carved the damned sigils on the floor with an enchanted knife. Her hand slipped at one point and bloodied the runes on the floor. She paid it no mind, bandaging her hand and continuing again. She didn’t dare use magic until the ritual was complete and she broke the circle. She endured her throbbing hand and at one point forgot about it, she was so focused on getting it right.

She took a deep breath and started the chant, just as Hermione and Ron sprinted into the clearing.

But Harriet had already started, the words coming out of her mouth frosty and hot in turns, some words tumbling out as heavy as a boulder, others coming out quickly and speedily like an eel.

Ron stopped Hermione, more aware than her about the dangers of interrupting a ritual.

“…in sumptus vitae meae,” she finished with a shout, slamming her hands on the sigils firmly, smearing it with blood. At one point, she had started to bleed from her injured hands.

“Harry, no!” Hermione screamed, held back by Ron’s hands on her shoulders. Of course, her friend could understand the Latin.

Smoke started rising from the blood and sigils, and from that smoke, something with tall with horns emerged.

Harry would be panicking, except she had gone so far from panic that she’d circled around to glassy calm. She’d be hyperventilating later.

If there was a later.

“At the cost of your life, huh,” a lovely, deep voice said inside the circle. “That’s a very interesting payment.”

The smoke cleared, and standing inside the circle was a man. Or as close to a man as a demon could get. His horns were long and curled back, the points curling at the tips and shining a dull red. His eyes shone yellow and his teeth were very sharp. His feet were cloven hooves and covered in shaggy fur, with a tail that flicked as he stood.

And his face. Harry instinctively shied away from looking at his too perfect, too beautiful face.

“Whatever is your trouble, lovely summoner?” the demon asked.

“Me and my people are at war,” she said, as boldly as she could manage. “And I am willing to pay anything for you to help us win.”

The demons beautiful face started to smile, a slash of a terrible smile on an otherwise inhumanly beautiful face.

“Break the circle, dear one. And I will seal the contract with you. You’ve already given me such lovely blood,” he whispered, a hypnotic ring in his voice.

Harry found herself moving despite Hermione and Ron’s shouts in her ears. She broke the circle with the knife still in her hand and the demon stepped out.

As he did, there was a ripple in the world like an invisible curtain, and the goats feet, horns and tail vanished. In his place was a man.

Still beautiful, but no longer inhumanly so. Enough of a change that she could look at his face without feeling that otherworldly aura.

“I am a chaos demon,” he declared. “And we seal these things with a kiss.”

The glassy calm broke, and Harry managed to squeak out, “ _What?”_ before the demons lips were on hers and she was consumed by the best kiss she’d ever had, all heat and passion.

After a minute, he pulled away and smiled at her dazed face.

“Stay here, my bride,” he said.

Harry crumpled to the forest floor and her best friends rushed to her, holding her hands and touching her shoulders. Hermione looked seconds away from crying. Ron looked like he wanted to wrap her up in bubble wrap.

“He just called me bride,” Harry managed weakly. “What just happened?”

Ron gave a tired huff into her neck, hugging her almost desperately.

Hermione gave an exhausted sigh.

“Harry,” she began slowly. “I don’t know how to tell you this, but I think a chaos demon just propositioned you.”

When Harry whined pathetically, Ron started to give little huffs of hysterical laughter.

.

* * *

.

The three of them staggered into Hogwarts, holding onto each other for support as well as comfort.

For Harry, she needed the help. The ritual took almost all of her magic. If she were a weaker witch, she would be dead.

“Ms. Potter,” Professor McGonagall said grimly. “Something has changed the battlefield.”

They looked into Hermione’s Seeing Mirrors, and Harry tried not to cringe at the sight of the stylishly dressed demon just. Walking and causing immense destruction with just a gesture.

It was one thing to know you’d summoned a monster, and another thing to see said monster in action.

“Oops,” she managed. “I guess he was more effective than I thought.”

That caught everyone’s attention.

“You did this? At what cost, Harry?” Neville asked.

Harry gave a wan smile, and he inhaled in understanding. Before he could open his mouth, the chaos demon came strolling back, hands in its pockets and a very cheery smile on its mouth.

“My bride,” he said. “I have killed all the leaders and destroyed their souls and happiness. I will, of course, wait for a week to see if they reform. After that, we will marry.”

“Ex-cuse me what?” Seamus said loudly. The noise of a couple hundred students causing chaos was defeaning.

The demon picked her up like she weighed like nothing and carried her off.

.

* * *

.

Harry thought the demon would eat her soul. Or even just eat her, she hadn’t thought demons were picky about corporeality.

Nowhere does _cuddling_ factor into it. Or hand feeding her grapes while making encouraging noises. Somehow, her fear just…went away when he was holding fruit to her mouth.

“You are too skinny,” he said, looking at her critically. “You must eat more.”

Uhm, no? They were at war…had been at war. Rationing was a thing. Still a thing while they solve the food issue because the first thing the Death Eaters had targeted were the Hogwarts Farms.

“If I eat more,” she explained to the demon currently holding her in his lap. “Then the children will eat less.”

He pouted. “And these…. _children_ …are important to you?” At her nod, he added, “then I will get you more food.”

He vanished for an hour, and returned with an entire freaking passel of pigs. Harry felt her mouth drop open.

“You will eat more?” he asked, like he hadn’t just solved their food problems for the next few weeks. If the keep some female alive and one or two boars, they can even keep some pigs for livestock and feed the entire school for years.

“Sure,” she said weakly. “I’ll eat.”

He looked so immeasurably smug that she wanted to hit him.

.

* * *

.

Outside the repaired grassy knoll beside the Great Lake, Harry enjoyed the rare sunshine and the lovely view of the lake.

Well. She tried to.

“Harry,” Hermione whispered. “Can I see the ritual you used?”

Harry had no qualms about that. Just. There was a chaos demon sleeping on her legs and she couldn’t move, or make much noise.

“Ask Kreacher,” she whispered back. “I don’t think I’m moving anytime soon.”

The chaos demon, who still hadn’t given his name – that was bothering her, hugged her thighs tighter, his face on her stomach. Harry oofed, leaning back to be more comfortable.

“Get me a book?” she asked her friend. “I’m stuck.”

Hermione looked bemused and handed over The Hobbit.

Harry, who actually hadn’t read the book yet, found herself combing her fingers through the demon’s hair as she read. Eventually, the heat of the sun and the cool wind combined with the firm weight on her stomach made her fall asleep, the book falling on her face.

Unseen to her, the demon’s tail flicked with pleasure.

.

* * *

.

A week filled with trials and burials later, she finally broke.

“What’s your name?” she asked. Hermione, opposite her in the sofa, crossed her arms frantically. Well, too bad for her, but Harry was tired of these unsaid things.

“It’s Reborn,” he rumbled. “And you are Harriet.”

Something about the way he said her name made her shiver.

“Yeah,” she said. “Why didn’t you eat my soul?”

He slow blinked at her. “That was not what you offered. You offered me your life. Not your death, or your soul, or even your blood and bone. Just your life. Obviously, in order for me to partake of your life, you have to be alive.”

“You are…feeding off me?” she asked.

“No,” he huffed. “I am experiencing it with you.”

Ron choked. “Isn’t that just marriage?” he coughed. His face was red. Harry’s own face was steadily going red.

The dem – Reborn nodded. “I know! It surprised everyone too. It was so forward.”

Harry covered her beet red face and groaned.

.

* * *

.

Reborn had to leave on some business. According to him, paperwork originated in hell and it was needlessly complicated. If he delayed further to log his contract with her, he’d have to fill out an extra fifty forms.

He kissed her very thorougly, rendering her stupid for a minute, before leaving.

Hermione then pounced, explaining what went wrong. Thank Merlin for Hermione, the lack of explanation reason was driving her crazy.

“You read it wrong,” she said. “And a good thing you did. Though how on earth you read ‘ _animae’_ as ‘ _vitae’_ , I wonder. It saved your life.”

Harry blinked at the horrific ritual book and sighed. “I was reading it sleep deprived and at one point, I think I was starting to hallucinate?”

“You and your luck, Harry,” Hermione said. “And did I scold you yet for summoning a chaos demon?”

Harry felt her _everything_ tense up. “…No,” she cringed.

She prepared for a lecture mostly done in yelling. She was braced for it.

Except Hermione hugged her tightly instead. “Thank you,” her dearest friend whispered.

Harry felt unintentionally teary. “For you and Ron? I would do it again,” she said into the bushy mane.

They both took a moment to compose themselves.

“So,” Hermione said in that tone that by long association, made Harry feel dread. Hermione only ever used that voice when she was being a little shit. “The chaos demon didn’t proposition you. You propositioned him first.”

“Oh my god,” Harry groaned. “You’re never gonna let this go, are you?”

She gave Harry such a look of mischief. “Never. I thought you were going to die, Harriet Potter. I’m going to say this to your wedding, and to all your birthdays.”

Thank Merlin that she was still alive to have birthdays.

She complained to Hermione just for the spirit of it, but was just as glad.

**Author's Note:**

> Honestly, if I can write smut, I would have made Reborn and Harriet have some hot steamy sex at one point.
> 
> I'm just blanking on the tags, tell me if I missed anything.


End file.
